The year is established by the relationship between this letter and the letter from
John Murray, 5 August [1867].

+

f2 5599.f2

CD had recommended Brehm et al. 1864--9, four volumes of which had been
sent to him by the publisher, for translation. See letter from
H. J. Meyer, 30 July 1867, letter to John Murray,
4 August [1867], and letter from John Murray, 5 August [1867] and
n. 3.